松材线虫危害后马尾松林下植被物种多样性变化及其与土壤养分的关系

Variation of Species Diversity of Understory Vegetation in Pinus massoniana Forest after Disturbance by Pine Wilt Disease and Its Relationship with Soil Nutrients

以合肥近郊蜀山森林公园受松材线虫危害的5块马尾松林为研究对象,分析了其林下植被物种多样性的变化及其与上层乔木、土壤性质的相关性。结果表明:林下植被物种多样性指数均与乔木层马尾松重要值存在显著的负相关性。在马尾松重要值大于80%的样地里,林下植被的物种多样性较低,在马尾松重要值小于80%的样地里,林下植被的物种多样性较高。草本层的物种多样性与马尾松重要值之间的相关性较为明显。5块样地里,灌木层的物种多样性均大于草本层的物种多样性,林下植被物种多样性的Margalef丰富度指数(D')、ShannonWiener指数(H')和Pielou均匀度指数(E')间互有相关性。土壤有机质、全磷、全氮、钙、镁均与林下植被的物种多样性指数存在显著的正相关,含水率与林下植被物种多样性指数存在显著的负相关。土壤养分与草本层物种多样性指数的相关性大于与灌木层物种多样性指数间的相关性。

An investigation of variation in understory species diversity and its relations to dominant tree and soil nutrients were conducted to understand the changes of understory vegetation in Pinus massoniana forest after disturbance by pine wilt dis- ease at Shushan Forest Park on suburban Hefei Province. The species diversity indices of understory vegetation are nega- tively correlated to the important value of arbor layer. The species diversity of understory vegetation was higher in stands with the important values （IV） of Pinus massoniana below 80% than that with IV over 80%. There is a significant rela- tionship between the species diversity of herb layer and the important value of P. massoniana. The species richness is higher in the shrub layer than in the herb layer. Species diversity indices of understory vegetationin are significantly and positively correlated with soil organic matter, total P, total N, Ca and Mg, while were negatively correlated with soil mois- ture content. Species diversity indices and soil nutrient in herb layer are larger than those in shrub layer.